Long-term complications and implant survival rates after cranioplastic surgery: a single-center study of 392 patients

Cranioplasty (CP) is a standard procedure in neurosurgical practice for patients after (decompressive) craniectomy. However, CP surgery is not standardized, is carried out in different ways, and is associated with considerable complication rates. Here, we report our experiences with the use of different CP materials and analyze long-term complications and implant survival rates. We retrospectively studied patients who underwent CP surgery at our institution between 2004 and 2014. Binary logistic regression analysis was performed in order to identify risk factors for the development of complications. Kaplan-Meier analysis was used to estimate implant survival rates. A total of 392 patients (182 females, 210 males) with a mean age of 48 years were included. These patients underwent a total of 508 CP surgeries. The overall complication rate of primary CP was 33.2%, due to bone resorption/loosening (14.6%) and graft infection (7.9%) with a mean implant survival of 120?±?5 months. Binary logistic regression analysis showed that young age (<?30 years) (p?=?0.026, OR 3.150), the presence of multidrug-resistant bacteria (p?=?0.045, OR 2.273), and cerebrospinal fluid (CSF) shunt (p?=?0.001, OR 3.137) were risk factors for postoperative complications. The use of titanium miniplates for CP fixation was associated with reduced complication rates and bone flap osteolysis as well as longer implant survival rates. The present study highlights the risk profile of CP surgery. Young age (<?30 years) and shunt-dependent hydrocephalus are associated with postoperative complications especially due to bone flap autolysis. Furthermore, a rigid CP fixation seems to play a crucial role in reducing complication rates.

     

Long-term outcome and survival of surgically treated supratentorial low-grade glioma in adult patients

Purpose  

The appropriate management of low-grade gliomas is still a matter of debate. So far, there are no randomized studies that analyze the impact of surgical resection on patient outcome. The value of the data obtained from the few retrospective reports available is often limited.     

Efficacy and safety of tonabersat, a gap-junction modulator, in the acute treatment of migraine: a double-blind, parallel-group, randomized study

The ability of tonabersat to relieve the symptoms of migraine attacks with or without aura was evaluated in a randomized, double-blind, placebo-controlled, multicentre, parallel-group study. Patients received 20 or 40 mg of tonabersat, or 50 mg of sumatriptan (positive control), or placebo at the onset of a moderate or severe attack. Headache intensity, relief and recurrence were recorded for 24 h after dosing. On the basis of primary or secondary efficacy measures, tonabersat did not provide a clinically or statistically significant advantage over placebo. Tonabersat generally was well tolerated and had no effect on vital signs, electrocardiogram recordings or laboratory values. The lack of efficacy may be a function of the slow absorption of tonabersat. As a consequence of slow absorption, daily administration of tonabersat as prophylaxis for migraine attacks is under investigation in ongoing studies.     

La cuerda dulce – a tolerability and acceptability study of a novel approach to specimen collection for diagnosis of paediatric pulmonary tuberculosis

Background  

Recent data demonstrate the utility of the string test for the diagnosis of sputum-scarce HIV-associated TB in adults. We hypothesized that, if well-tolerated by children, this simple tool might offer a breakthrough in paediatric TB diagnosis. Thus the objective of this study, undertaken in the paediatric service of the Hospital Nacional Dos de Mayo, Lima, Perú, was to determine the tolerability and acceptability of the string test to paediatric TB suspects, their parents and nursing staff.     

Acute haemorrhage into a microcystic meningioma leading to cerebral herniation

Low-grade (WHO level I) meningiomas are slow-growing, benign tumours typically presenting with unspecific symptoms (e.g. headache), seizures, cranial nerve compression and neuropsychological symptoms determined by location and size of the lesion. Haemorrhagic onset and sequelae are rare, and have been described infrequently. This is a case of a 50-year-old male presenting with signs of tentorial herniation secondary to hyperacute intratumoural haemorrhage (ITH) into a previously undiagnosed meningioma. Emergency surgical decompression and exstirpation of the lesion helped to achieve a favourable outcome. ITH has been described in all including benign intracranial neoplasms. Factors associated with a higher risk for haemorrhage in meningiomas are discussed. Though haemorrhages associated with meningiomas have been reported, ITH into low-grade meningiomas leading to herniation remains a rarity. Bearers of known lesions and their treating physicians who opt for conservative or delayed treatment should be aware of this remote complication.     

Columnar specificity of microvascular oxygenation and volume responses: implications for functional brain mapping

Cortical neurons with similar properties are grouped in columnar structures and supplied by matching vascular networks. The hemodynamic response to neuronal activation, however, is not well described on a fine spatial scale. We investigated the spatiotemporal characteristics of microvascular responses to neuronal activation in rat barrel cortex using optical intrinsic signal imaging and spectroscopy. Imaging was performed at 570 nm to provide functional maps of cerebral blood volume (CBV) changes and at 610 nm to estimate oxygenation changes. To emphasize parenchymal rather than large vessel contributions to the functional hemodynamic responses, we developed an ANOVA-based statistical analysis technique. Perfusion-based maps were compared with underlying neuroanatomy with cytochrome oxidase staining. Statistically determined CBV responses localized accurately to individually stimulated barrel columns and could resolve neighboring columns with a resolution better than 400 microm. Both CBV and early oxygenation responses extended beyond anatomical boundaries of single columns, but this vascular point spread did not preclude spatial specificity. These results indicate that microvascular flow control structures providing targeted flow increases to metabolically active neuronal columns also produce finely localized changes in CBV. This spatial specificity, along with the high contrast/noise ratio, makes the CBV response an attractive mapping signal. We also found that functional oxygenation changes can achieve submillimeter specificity not only during the transient deoxygenation ("initial dip") but also during the early part of the hyperoxygenation. We, therefore, suggest that to optimize hemodynamic spatial specificity, appropriate response timing (using < or =2-3 sec changes) is more important than etiology (oxygenation or volume).     

1-year performance of a defibrillation lead with a small electrode surface for high impedance pacing: a randomized,controlled study

A small electrode surface reduces pacing current drain and can extend generator longevity. The study evaluated the performance of a tined, quadripolar defibrillation lead (model 6944) that has a small-surfaced, steroid-eluting electrode tip for high impedance pacing. In a prospective, controlled study, 34 patients with conventional ICD indications were randomized one to one to receive the high impedance model 6944 or a tined defibrillation lead with a conventional sized, steroid-eluting electrode tip model 6942. Lead performance was evaluated at implant, prior to hospital discharge, and 1, 3, 6, and 12 months thereafter. Baseline characteristics did not differ significantly between patients implanted with lead model 6942 (n = 16) or model 6944 (n = 17). One patient randomized to receive the model 6942 was excluded from the study and was implanted with an active-fixation lead after stable lead positioning was neither possible with the 6942 nor with the 6944 electrode. No other lead related adverse events were observed. At implant, there were no significant differences between pacing thresholds, sensing performance, defibrillation impedances, and defibrillation thresholds in both groups, but pacing impedance of the model 6944 (988.6 +/- 217.7 omega) was approximately twice as high as high as in the model 6942 (431.7 +/- 83.7 omega; P < 0.0001). This difference remained highly significant throughout the observation period of 12 months, while R wave amplitudes and pacing thresholds remained equal in both lead models. The use of a tined defibrillation lead with a small, steroid-eluting electrode tip appears safe and results in a high pacing impedance without compromising system performance.     

Filters for radiation reduction: a comparison

Aluminum, yttrium, copper, and R-filters were evaluated with respect to effective beam energy, entrance radiation exposure to the skin, x-ray tube loading, and the quality of resultant radiographs. Since all filters yielded acceptable radiographs, a figure of merit was developed to determine which filter delivered the lowest entrance radiation exposure for the lowest increase in x-ray tube loading. The figure of merit indicated that the best results were obtained with the 0.1-mm Cu filter with 2 mm Al at 60-105 kVp and with the 0.2-mm Cu filter with 2 mm Al at 105-120 kVp. Cu filters produced radiographs with quality comparable to that of R- or Y filters. Cu filters are inexpensive alternatives to rare-earth filters and yielded a reduction in radiation exposure with less x-ray tube loading.     

Short- and long-term results following implantation of the new Wiktor stent in acute coronary occlusion following PTCA

Ten patients, two women and eight men, were treated with the new balloon-expandable Wiktor Stent for acute coronary occlusion after PTCA. Two patients presented with an acute myocardial infarction. Stents with a diameter of 3.0 or 3.5 mm were implanted into the right coronary artery (n = 7), the left anterior descending (n = 2) artery, and the left circumflex coronary artery (n = 1). Stent implantation in the target segment was successful in all cases. Afterwards, patients received coumadine for 3 months and 100 mg acetylsalicyclic acid per day. We observed one acute occlusion after 8 h. Late occlusion occurred in two patients after cessation of anticoagulation within 3 weeks. Control angiography after 6 months in seven patients revealed stenosis within the stent in two cases.     

Edema and brain trauma

Brain edema leading to an expansion of brain volume has a crucial impact on morbidity and mortality following traumatic brain injury (TBI) as it increases intracranial pressure, impairs cerebral perfusion and oxygenation, and contributes to additional ischemic injuries. Classically, two major types of traumatic brain edema exist: "vasogenic" due to blood-brain barrier (BBB) disruption resulting in extracellular water accumulation and "cytotoxic/cellular" due to sustained intracellular water collection. A third type, "osmotic" brain edema is caused by osmotic imbalances between blood and tissue. Rarely after TBI do we encounter a "hydrocephalic edema/interstitial" brain edema related to an obstruction of cerebrospinal fluid outflow. Following TBI, various mediators are released which enhance vasogenic and/or cytotoxic brain edema. These include glutamate, lactate, H(+), K(+), Ca(2+), nitric oxide, arachidonic acid and its metabolites, free oxygen radicals, histamine, and kinins. Thus, avoiding cerebral anaerobic metabolism and acidosis is beneficial to control lactate and H(+), but no compound inhibiting mediators/mediator channels showed beneficial results in conducted clinical trials, despite successful experimental studies. Hence, anti-edematous therapy in TBI patients is still symptomatic and rather non-specific (e.g. mannitol infusion, controlled hyperventilation). For many years, vasogenic brain edema was accepted as the prevalent edema type following TBI. The development of mechanical TBI models ("weight drop," "fluid percussion injury," and "controlled cortical impact injury") and the use of magnetic resonance imaging, however, revealed that "cytotoxic" edema is of decisive pathophysiological importance following TBI as it develops early and persists while BBB integrity is gradually restored. These findings suggest that cytotoxic and vasogenic brain edema are two entities which can be targeted simultaneously or according to their temporal prevalence.